Method and apparatus for annealing and cooling sheet glass



Aug. 3l 1926.

W. L. MONRO METHODv AND APPARATUS FOR ANNEALING AND COOLING S-HEET GLASS 2 Sheets-Sheet 1 Filed Feb. 12, 1924 m@ m w26. n,597,994 W. L. MONRQ4 METHOD VAND APPARATUS FOR ANNEALING/ND COOLING SHEET GLASS Filed Feb. l2, 1924 2 Shee ts-Sheet 2 narran sTA'rss rnfrsNi-f o1-rica l mmm L. nonno, or rrrrsnuaernrnnnsrnvanm, .ass'IGNoa uro ltviunow enass v`111.11131111111111-coinrnmr, or PITTSBURGH,

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manson am Prunus :son

PENNSYLVANIA, A CORPOBTIN QF NEW ammessa med February 12, 1924. serial nel essaie,

I-Ieretofore glass leers .have been provided with a source of heated gases, which gases' ltravel through the leer tunnel concurrently and in the same direction with the glass and serve to decrease the; rate at which the glass loses temperature, thus slowly annealing and cooling it and preventing breakage. The

only reason for providing these heated gases is, as above stated, to prevent the too rapid cooling of the glass sheets, since a leer is essentially an apparatus for absorbing heat from the glass.

I provide a leer tunnel through which the glass is moved in one direction, while streams of gases above and below the glass are passed through the tunnel in the opposite direction. Thus streams of air or gases, previously heated or not, may be introduced at the delivery end of the leer and passed toward the end at which the glass enters. As

the air or gas travels through the leer tunnel, it becomes hotter and hotter, so that when it comes into contact with the glass just entering the leer,

temperature thatl the glass does not break, but is cooled slowly. With a leer of this type it is unnecessary to .supply the large quantity of heat which is required in leers j, of ordinary construction.

In the accompanying drawings illustrating the preferred embodiments of my invention;

Figure 1 is a vertical longitudinalsection through a portion of a leer embodying my invention;

Figures 2 and 3 are similar viewsv showing modiiied forms of the invention, 1nltended to more nearly equalize temperature conditions above and below the glass level;

Figure 4 is al section on the line IV--IV of Fig. 2` and v Figure 5-is asection on the line V-V oi Fig. 4,' showing a cooler as installed in the eer.

In the embodiment of the invention illustrated in Figure 1, there is shown a leer it is at a high enough i tunnel 2 havingA leer rods construction adapted to carry the glass .from right to left 'as i viewed in l the drawing-` When lthe leer`is in operation, the glass on' the rods' forms a substantially continuous division wall dividing the leer tunnel 2 into two passages; one above and one below the glass. Air, enters the leer tunnel adjacent the delivery end thereof and travels from left to right as viewed in the drawings. The passage of the gases through the leer is accomplished Mettmann eotjrn'ejsnnnremss.

3 of'. any suitable I or other suitable cooling fluid, -i

and controlled by suction pipes 4: having dampers 5 therein and connected to cross iues 6 leading to the spaces above and below the glass at or near its point of ventry into the leer tunnel. The suction pipes 4 are connected to a suction `ian or stack (not shown) for providing a suitable draft. By regulatingthe dampers 5, the relative velocity of the gaseous streams above and below the lass level may be varied in such manner as to substantially equalize the rate of heat loss from the two surfaces of the glass, thus producing afiat eration, iiat'hot glass is supplied to the leer through an opening 7 adjacent the end at which the gases are sucked from the leer v tunnel.

Inthis, as in' any other leer, the gases tend to rise toward the top as they become heated, so that there is a general tendency for the lower portion of the tunnel to remain at a temperature lower than the upper portion thereof and the dampers 5 may be adjusted to offset this natural tendency preferably by providing greater draft on the lower stream than on the upper stream.

Figures 2 and 3 illustrate other ways of oiisetting the same tendency. Figure 2 shows an apparatus similar to Figure 1, except that coolers 8 connected with iuid supply lines 9 having regulating valves 10` are provided in the upper portion of the leer tunnel and serve to cool As shown in Fig.` 4, these coolers preferably extend the entire width of the leer tunnel and are preferably constructed as shown in Fig. 5, sincethis form of cooler insures `a uniform cooling effect across the leer.

Another method of accomplishing the the gases therein.

. ing air orgas,

` streams above and a leer tunnel 1n a between the rods.

-of the leer 'tunnel same result is shown in Figure 3, wherein i the fioor ofthe leer tunnel is provided with a heating flue or muiile 11 having a gas conduit 12 provided with a damper 13 at one or both ends thereof. Heated gases from passed through the muiile 11 and serve tov supply heat to the fioor, so

that the temperature from top to bottom is' more nearly equalized. Preferably the heated gases in the muilie 11 travel in the same direction as the glass. Gas inlet ues 4* having dampers 5a and terminating, in .cross-lines 6a may be provided. for the enterand are particularly desirable if the entering fluid is pre-heated. If preheated air is passed through the lower heating flue it may be fed intothe glass outlet end of the leer, both above and below theA glass. I may also combine the features of Figures 2 and 3 and luse both the coolers above the glass and the heating iiue beneath. r air or gases heated in the lower :flue may be fed in with the air entering the glass outlet' end in unequal ratios, more being fed in Lbelow than above.

It will be further understood that the heating iiue's of Figure 3 may be applied "to any embodiment of the invention.. In

any case itwill be found desirable to make the openings through which the glass enters as tight as possible in order to prevent the ingress of air or gases in such quantities as to cause a short-circuiting of `the iiow. In the drawings it will be seen that a side wall of each cross iiue lies very4 close to the leer rods and also has its edge portion bent over to reduce the openingas much Ias possible. If desired, the edge port-ions on the lower fiues may be shaped to fit up I thus provide for annealing and cooling sheet glass and passing cooling gases in below the glass through i direction opposite to the direction of travel of the glass, and may vary the heat content of one of the streams by means oth .r than the glass itself. By suitable regulation of such means the coolingy effect of the two streams may be so regulated as to substantially balance the rate of heat loss from the two faces of the glass, whereby a iiat and unwar'ped product is produced.

While my invention makes it unnecessary to heat the entering gases to the usual entering temperature of -approximately 1000 F., it will myself to the use of unheated gases, as it may-be desirable, under certain conditions, to use warm gases. By so doing, the length maygenerally be shortened considerably.

While I have illustrated the preferred form of my invention, it will be understood that it is not limited to the illustrated embe understood that I do not limit bodiment, but ma be otherwise embodied within the scope o thefollowing claims.

I claim:

1. In the method of annealing and cooling sheet glass, the steps consisting of passing fiat hot glass through a leer tunnel in one direction, and causing gaseous fluid initially cooler than the glass to travel through substantially the entire length of the tunnel in the opposite direction, and in contact' with the glass, substantially as described.

2. Iny the methodof annealing and cooling sheet glass, the steps consisting of passin flat hot glass through a horizontally exten ing leer tunnel in one direction, and causing gaseous fluid to travel through the tunnel in the opposite direction Iin streams, one above and one below the glass, substantially as described.

3'. In the method of annealing and cooling `sheet glass, the steps consisting of introducing flat hot glass to a leer tunnel, passing it therethrough in -one direction, causing gaseous fluid to travel through the tunnel in the other direction in streams, one on each side of the glass, and varying the cool ing eiiect of onestream relative to the other, substantially as described.

4. In the method of annealing and cooling sheetl glass, the steps consisting of introducing flat hot glass to a leer tunnel, passing it therethrough in one direction, causing gaseous fluid to travel through the tunnel in the other direction in streams, one on each side of the glass, and varying the normal cooling eiect of one stream relative to the other in amounts suiicient to substantially equalize the rate of heatl loss from the two faces of the glass sheet, substantially as described.

5. In the method of annealing and cooling sheet glass, the steps consisting of introducing fiat hot` extending leer tunnel, passing it therethrough in one direction, causing gaseous fluid to travel through the tunnel in the other direction in streams above and below theglass, and amplifying the heat absorption capacity of the upper stream relative tothe lower stream, substantially as described. ,l

6. Apparatus for annealing and cooling sheet glass, including a leer tunnel, means for passing glass therethrough in one direction, and means for causing gaseous fluid to travel through' the tunnel in the other direction in streams on each side of the glass, substantially as described.

7. Apparatus for annealing' and cooling sheet glass, including a .leer tunnel, means for passing glass therethrough in onedirection, means for causing gaseous fluid to travel through the tunnel in the opposite direction in streams on each side of the glass, and means for varying the cooling effect of one of the streams, substantially as tunnel in the opposite direction in streams described. above and below the glass, and means or 8. Apparatus for annealing and cooling amplifying the normal cooling eii'ect of the 10 sheet glass, including a horizontally extendupper stream, substantially as described.

5 ing leer tunne, means for passing glass In testimony whereof l have hereunto set therethrough in one direction, means for my hand.

causing gaseous fluid to travel through the WILLIAM L. MONRO. 

